A compressor for a refrigeration circuit compresses refrigerant, and usually lubricating oil is contained in the refrigerant. The lubricating oil contained in the refrigerant has not only a function for lubricating slidable surfaces, bearings, etc. in the compressor but also a function for sealing the slidable surfaces. However, if the lubricating oil is circulated over the entire refrigeration circuit, generally the lubricating oil becomes a factor decreasing the cooling ability of the refrigeration circuit.
Therefore, a compressor incorporating a lubricating oil separator thereinto is known. The lubricating oil separator separates lubricating oil from compressed refrigerant on the route through which the refrigerant compressed in the compressor is introduced from a discharge chamber to a discharge port. More concretely, the lubricating oil separator has a separation chamber disposed between the discharge chamber and the discharge port, and it separates the lubricating oil from the compressed refrigerant which is introduced from the discharge chamber into the separation chamber through a spouting hole. The lubricating oil separated from the refrigerant is stored in an oil storage chamber formed below the separation chamber (for example, Patent document 1).    Patent document 1: JP-A-11-82352